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Competitive athletes completed two studies of 2-h steady-state (SS) cycling at 70% peak O 2 uptake followed by 7 kJ/kg time trial (TT) with carbohydrate (CHO) intake before (2 g/kg) and during (6% CHO drink) exercise. In Study A, 12 subjects received either 6 mg/kg caffeine 1 h preexercise (Precaf), 6× 1 mg/kg caffeine every 20 min throughout SS (Durcaf), 2× 5 ml/kg Coca-Cola between 100 and 120 min SS and during TT (Coke), or placebo. Improvements in TT were as follows: Precaf, 3.4%(0.2–6.5%, 95% confidence interval); Durcaf, 3.1%(− 0.1–6.5%); and Coke, 3.1%(− 0.2–6.2%). In Study B, eight subjects received 3× 5 ml/kg of different cola drinks during the last 40 min of SS and TT: decaffeinated, 6% CHO (control); caffeinated, 6% CHO; decaffeinated, 11% CHO; and caffeinated, 11% CHO (Coke). Coke enhanced TT by 3.3%(0.8–5.9%), with all trials showing 2.2% TT enhancement (0.5–3.8%; P< 0.05) due …